[logger] Use raw pointer for task log buffer to match tx_buffer pattern

esphome/components/esp8266/preferences.cpp

@@ -12,6 +12,7 @@ extern "C" {
 #include "preferences.h"
 
 #include <cstring>
+#include <memory>
 
 namespace esphome::esp8266 {
 
@@ -142,8 +143,16 @@ class ESP8266PreferenceBackend : public ESPPreferenceBackend {
       return false;
 
     const size_t buffer_size = static_cast<size_t>(this->length_words) + 1;
-    SmallBufferWithHeapFallback<PREF_BUFFER_WORDS, uint32_t> buffer_alloc(buffer_size);
-    uint32_t *buffer = buffer_alloc.get();
+    uint32_t stack_buffer[PREF_BUFFER_WORDS];
+    std::unique_ptr<uint32_t[]> heap_buffer;
+    uint32_t *buffer;
+
+    if (buffer_size <= PREF_BUFFER_WORDS) {
+      buffer = stack_buffer;
+    } else {
+      heap_buffer = make_unique<uint32_t[]>(buffer_size);
+      buffer = heap_buffer.get();
+    }
     memset(buffer, 0, buffer_size * sizeof(uint32_t));
 
     memcpy(buffer, data, len);
@@ -158,8 +167,16 @@ class ESP8266PreferenceBackend : public ESPPreferenceBackend {
       return false;
 
     const size_t buffer_size = static_cast<size_t>(this->length_words) + 1;
-    SmallBufferWithHeapFallback<PREF_BUFFER_WORDS, uint32_t> buffer_alloc(buffer_size);
-    uint32_t *buffer = buffer_alloc.get();
+    uint32_t stack_buffer[PREF_BUFFER_WORDS];
+    std::unique_ptr<uint32_t[]> heap_buffer;
+    uint32_t *buffer;
+
+    if (buffer_size <= PREF_BUFFER_WORDS) {
+      buffer = stack_buffer;
+    } else {
+      heap_buffer = make_unique<uint32_t[]>(buffer_size);
+      buffer = heap_buffer.get();
+    }
 
     bool ret = this->in_flash ? load_from_flash(this->offset, buffer, buffer_size)
                               : load_from_rtc(this->offset, buffer, buffer_size);

esphome/components/logger/logger.cpp

@@ -1,8 +1,5 @@
 #include "logger.h"
 #include <cinttypes>
-#ifdef USE_ESPHOME_TASK_LOG_BUFFER
-#include <memory>  // For unique_ptr
-#endif
 
 #include "esphome/core/application.h"
 #include "esphome/core/hal.h"
@@ -199,7 +196,8 @@ inline uint8_t Logger::level_for(const char *tag) {
 
 Logger::Logger(uint32_t baud_rate, size_t tx_buffer_size) : baud_rate_(baud_rate), tx_buffer_size_(tx_buffer_size) {
   // add 1 to buffer size for null terminator
-  this->tx_buffer_ = new char[this->tx_buffer_size_ + 1];  // NOLINT
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->tx_buffer_ = new char[this->tx_buffer_size_ + 1];
 #if defined(USE_ESP32) || defined(USE_LIBRETINY)
   this->main_task_ = xTaskGetCurrentTaskHandle();
 #elif defined(USE_ZEPHYR)
@@ -212,11 +210,14 @@ Logger::Logger(uint32_t baud_rate, size_t tx_buffer_size) : baud_rate_(baud_rate
 void Logger::init_log_buffer(size_t total_buffer_size) {
 #ifdef USE_HOST
   // Host uses slot count instead of byte size
-  this->log_buffer_ = esphome::make_unique<logger::TaskLogBufferHost>(total_buffer_size);
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->log_buffer_ = new logger::TaskLogBufferHost(total_buffer_size);
 #elif defined(USE_ESP32)
-  this->log_buffer_ = esphome::make_unique<logger::TaskLogBuffer>(total_buffer_size);
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->log_buffer_ = new logger::TaskLogBuffer(total_buffer_size);
 #elif defined(USE_LIBRETINY)
-  this->log_buffer_ = esphome::make_unique<logger::TaskLogBufferLibreTiny>(total_buffer_size);
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->log_buffer_ = new logger::TaskLogBufferLibreTiny(total_buffer_size);
 #endif
 
 #if defined(USE_ESP32) || defined(USE_LIBRETINY)

esphome/components/logger/logger.h

@@ -412,11 +412,11 @@ class Logger : public Component {
 #endif
 #ifdef USE_ESPHOME_TASK_LOG_BUFFER
 #ifdef USE_HOST
-  std::unique_ptr<logger::TaskLogBufferHost> log_buffer_;  // Will be initialized with init_log_buffer
+  logger::TaskLogBufferHost *log_buffer_{nullptr};  // Allocated once, never freed
 #elif defined(USE_ESP32)
-  std::unique_ptr<logger::TaskLogBuffer> log_buffer_;  // Will be initialized with init_log_buffer
+  logger::TaskLogBuffer *log_buffer_{nullptr};  // Allocated once, never freed
 #elif defined(USE_LIBRETINY)
-  std::unique_ptr<logger::TaskLogBufferLibreTiny> log_buffer_;  // Will be initialized with init_log_buffer
+  logger::TaskLogBufferLibreTiny *log_buffer_{nullptr};  // Allocated once, never freed
 #endif
 #endif
 

esphome/core/helpers.h

@@ -371,15 +371,13 @@ template<typename T> class FixedVector {
 /// @brief Helper class for efficient buffer allocation - uses stack for small sizes, heap for large
 /// This is useful when most operations need a small buffer but occasionally need larger ones.
 /// The stack buffer avoids heap allocation in the common case, while heap fallback handles edge cases.
-/// @tparam STACK_SIZE Number of elements in the stack buffer
-/// @tparam T Element type (default: uint8_t)
-template<size_t STACK_SIZE, typename T = uint8_t> class SmallBufferWithHeapFallback {
+template<size_t STACK_SIZE> class SmallBufferWithHeapFallback {
  public:
   explicit SmallBufferWithHeapFallback(size_t size) {
     if (size <= STACK_SIZE) {
       this->buffer_ = this->stack_buffer_;
     } else {
-      this->heap_buffer_ = new T[size];
+      this->heap_buffer_ = new uint8_t[size];
       this->buffer_ = this->heap_buffer_;
     }
   }
@@ -391,12 +389,12 @@ template<size_t STACK_SIZE, typename T = uint8_t> class SmallBufferWithHeapFallb
   SmallBufferWithHeapFallback(SmallBufferWithHeapFallback &&) = delete;
   SmallBufferWithHeapFallback &operator=(SmallBufferWithHeapFallback &&) = delete;
 
-  T *get() { return this->buffer_; }
+  uint8_t *get() { return this->buffer_; }
 
  private:
-  T stack_buffer_[STACK_SIZE];
-  T *heap_buffer_{nullptr};
-  T *buffer_;
+  uint8_t stack_buffer_[STACK_SIZE];
+  uint8_t *heap_buffer_{nullptr};
+  uint8_t *buffer_;
 };
 
 ///@}